This userscript groups image thumbnails of similar images together to one thumbnail with a button to toggle all the other images in a group. For example, this is useful when multiple variants of the same image or similar images by the same artist are uploaded shortly in succession.
Example: Without userscript
Only images with the same artist(s) are grouped. The similarity is obviously calculated from the images' tags, therefore it will be less accurate for images with few tags. Of course the amount of images per page doesn't change, therefore you won't any see more images than before. The benefit is that the page isn't cluttered by multiple thumbnails of the same image.
You can configure several aspects of the script:
Exclude images without artists: Don't group images without artist. (Default: false)
Tresholds: How similar the images should be to be grouped. If set to 0, all images by the same artist(s) are grouped. (Default: 0.7, 0.5, 0.5)
Adjust for tagcount: Apply fancy mathematics to (hopefully) compensate for under- and overtagged images. (Default: true)
Disable on artist tag pages: Don't group images on /tags/artist:… pages. This is useful when you set the treshold to 0 to avoid grouping all images on that page. (Default: false)
Weights: Different tags and tag namespaces can have different weights that they contribute to the similarity measure. These are set by default to group images with the same characters and filter out certain tags that would skew the calculation.
Sorting: Set the sorting of images within a group. Options are: upload time (original order); score; and highest score first, then by similarity to the previous image (default)
You need Greasemonkey for Firefox or Tampermonkey for Chrome (or equivalent add-ons that can load userscripts).
0.5.1: "Temporary" fix for expand button taking up a new row
0.5.0: Updated for Derpibooru's new design, doesn't use jQuery anymore
0.4.1: Now works with JS strict mode
0.4.0: First public release (see Gist for previous changes)
~Also check out my other userscripts: Tag suggestions, Images per page dropdown
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